A micromammal archaeological sequence (2120 f 120 to 780 f 100 years BP) from Inca Cueva 5 site (23 05' S - 65 27' W; 3700 m.a.s.l., Jujuy Province, Argentina) was studied. The following mammalian taxa were recorded: Order Didelphimorphia, Family Didelphidae, Thylamys cf. T. pallidior; Order Rodentia, Family Muridae, Akodon cf. A. albiventer, Andinomys edax, Auliscomys sublimis, Calomys lepidus, Neotomys ebriosus, Phyllotis sp.; Family Caviidae, Cavia cf. C. tschudii, Galea musteloides; Family Abrocomidae, Abrocoma cinerea; Family Chinchillidae, Lagidium viscacia; Family Octodontidae, Octodontomys gliroides. The taphonomy indicates that the sequence is an owl pellet accumulation inside the cave. The general landscape corresponds to the oriental border of the Puna steppe, with scattered shrub and low brush vegetation. Near the site there are small tree groups of Polylepis australis as well as small streams covered with grass and ciperaceous vegetation known as «vegas». Al1 the recorded taxa at Inca Cueva 5 exist today in Puna and Prepuna environments from Jujuy and Salta Provinces and southem Bolivia, excepting Cavia cf. C. tschudii. The modem records of this species in northem Argentina and southern Bolivia come from localities with high montane bunchgrass prairies and forests of the humid Yungas phytogeographical region. The presence of this species in the sequence suggests wetter climatic conditions on this region when the archaeological site was originated. Later drier conditions, caused probably by anthropic influence in the last 500 years, produced the retraction of Cavia tschudii to the moist eastern side of the Andes and its disappeareance of the Puna areas.